Liquid Properties and Surface Tension

18. The second effect of air-aether motion: separate one body from another and purge liquids

When the particles of terrestrial bodies, especially liquids, are confusedly joined together, the air-aether globules tend to:

• separate some from others
• distinguish them into various bodies
• mix others more accurately*
  • They arranging them in such a way that each droplet of the liquid formed from them is entirely similar to all other droplets of the same liquid.

When air-aether globules move through the passages of liquid terrestrial bodies, they constantly displace the earth-aether particles that come in their way.

The earth-aether particles become arranged among the others so that they no longer oppose the motions of each other. If they cannot be arranged in this way, they will be separated from the rest.*

Thus, we observe that from dregs, certain liquids are expelled:

• upward
  • This is attributed to levity
• downward
  • This is attributed to gravity
• the sides of the vessel

The wine subsequently becomes clarified, although it still consists of various particles. It appears transparent and no denser at the bottom than at the top.

The same should be assumed for other pure liquids.

19. The third effect of air-aether motion: make suspended drops of liquids round

Meteors explained that the third effect of air-aether globules is to make drops of liquids, suspended in the air or another liquid different from them, round.

These air-aether particles have to travel much longer around a water droplet than through physical air.

To resume their usual straight-line path, they press on the droplet to make it perfectly round.

• This is because if one part of the droplet protrudes, then it would deflect the air-aether motion and prevent its straight-line movement and cause it to impact that protruding part more.
• This will cause the air-aether to push the protruding part towards the center of the droplet.

Likewise, if any part of the droplet is sunk closer to the center than the rest of the surface, the internal air-aether in the droplet itself [which is also rotating?] will push that sunken area more forcefully from the center.

And so all air-aether contribute to making a spherical droplet.

A straight line is most uniformly inflected in each of its points when it degenerates into a circular curve.